1. Field of the Invention
The present invention relates to a screw design, particularly to a screw with waved thread.
2. Description of the Related Art
Referring to FIGS. 1 and 2, a conventional screw 1 comprises a head 11, a shank 12 connecting to the head 11, and a plurality of threads 13 spirally disposed on the shank 12; wherein, each thread 13 has an upper flank 131 and a lower flank 132 both extending from the shank 12, and an arris 133 disposed between the upper flank 131 and the lower flank 132. Moreover, the threads 13 have a plurality of notches 134 disposed thereon, and a thread portion 135 is formed between any two notches 134. Furthermore, the thread portions 135 are interlaced and are disposed in sawtooth shape, and the peaks 136 of the thread portions 135 are interlaced and are therefore located above or under the waved arris 133.
Due to the thread portions 135 interlaced and disposed in a sawtoothed shape, the area of the conventional screw 1 enabling the object to be cut increases. With the assistance of the aforesaid point, while in operation, the object will be rapidly cut and the screwing speed will enhance. Moreover, when the thread portions 135 in a sawtoothed shape blocks, the conventional screw 1 can be prevented from loosening or dropping out after it is screwed. However, while in operation, the conventional screw 1 still deserves to be improved, so the present invention is invented.